As the first CRM at our organization, Fundly has been transformational, especially for organizing paid and free events with online signups.
Fundly is a young CRM, and still has some significant bugs or inadequacies: for example, patrons can't pay an invoice that Fundly sends, so we have to do a workaround with PayPal. But their staff is very open to troubleshooting, which helps.
A great resource, but glitchy in this early stage—be ready to work with their customer service team to customize Fundly to your needs.
Fundly primarily makes our event organizing much more efficient, aggregating all attendees in one place and logging their past attendance. As an arts organization that does regular public events, this is hugely helpful.